The United States has redirected four commercial vessels since July 14, marking the first operational enforcement actions of the reinstated naval blockade against Iran, according to the US Central Command (CENTCOM).
The military command also reported disabling one vessel and boarding another to ensure compliance with the new restrictions.
The enforcement actions follow a sharp policy reversal by the US administration, which reinstated sanctions on Iranian oil exports and ordered the naval blockade just days after a brief period of relaxed restrictions.
The operation, directed by President Donald Trump, aims to curb Iranian maritime activity in the Gulf of Oman and the Strait of Hormuz.
Markets are monitoring the escalation closely, with shipping risk premiums remaining elevated in energy and freight sectors.
The blockade adds to existing tensions in the region, where recent explosions at the Iranian port of Chabahar have already heightened concerns over supply chain disruptions.